By way of example, locking assemblies having mechanical position signaling devices (EP 0 789 925 B1) and signaling switch assemblies having position signaling devices in the form of electrical signaling switches are known from low-voltage switching technology. Such locking assemblies and signaling switch assemblies are coupled by way of a coupling arrangement of this generic type to a switching shaft, which is provided with a coupling piece composed of plastic, of an electrical switch in the form of a low-voltage circuit breaker.
The document EP 0 789 925 B1 discloses that the locking assembly described there having mechanical position signaling devices is arranged on a mount. The mount can be attached to an outer wall of a plug-in frame or to an adaptor plate, which is used as a supporting member and is held externally on the electrical switch, depending on the type of installation of the electrical switch (push-in version or permanently installed version).
The known coupling arrangement designed such that the signaling switch assembly, which is arranged in a fixed position on an inner wall of a plug-in frame, the locking assembly which is attached in a fixed position to an outer wall of the plug-in frame or optionally—by way of an irreversible modification of the signaling switch assembly—also both assemblies can be jointly coupled to the switching shaft of the electrical switch which is arranged in the plug-in frame such that it can be moved. In this case, the electrical switch can be moved in a known manner in the plug-in frame from a disconnected position, in which both auxiliary and main contacts are disconnected, via a test position, in which only the auxiliary contacts are connected, to an operating position, in which both the auxiliary and the main contacts are connected. The electrical switch can be switched, with the switching shaft being rotated, in the operating position, in the test position and in the disconnected position.
The known coupling arrangement uses two couplings in the operating position and in the test position to transmit the rotational movement of the switching shaft to the signaling switch assembly during switching of the electrical switch, and can be irreversibly changed by a modification such that, in the operating position, it additionally passes on the rotational movement of the switching shaft to the locking assembly, as well. This known coupling arrangement comprises a large number of individual parts and involves a correspondingly large amount of assembly effort.